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    <script>
        document.write("怎");
        var name1= "elio";
        let name2= "oliver";
        const Pi=3.14;
        var t;   
           
    
        console.log(name1);
        console.log(name2);

         t=name1;
        name1=name2;
        name2=t;
    
            console.log(name1);
            console.log(name2);
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